After decades of waiting, the electoral systems anoraks are having a field day; everyone is now talking about proportional representation. But PR is not just one of many reforms to mend our broken political system; it transforms everything. Without it there will be no new politics.

And here is the anoraks' problem, they can argue forever about the pros and cons of different systems, but what is hard to communicate, but much more important, is the cultural shift in our politics that PR enables.

First past the post (FPTP) is the electoral system of the bygone age of Fordism, the age of mass production, of two social classes and therefore just two old political parties. It is the bureaucratic and clunking system of two tribes that go to war; tribes that are controlled and ordered by the party machines. There is no public debate, we just take it or leave it. It is yah boo and adversarial. It feeds the tyranny of middle England whereby a handful of voters in a handful of seats determine every election outcome. It gives all power to the fickle and the people who lead them; Rupert Murdoch of the Sun and Paul Dacre of the Mail. In the process core supporters are taken for granted and ignored. It leads to the rise of the BNP. Finally, FPTP is the politics of ends over means; it doesn't matter that governments get 100% power based on 25% of the vote; it delivers strong government.

But that myth has been exploded. FPTP is revealed as weak because the world has moved on. The culture of deference that gave it oxygen has gone. Instead of command and control you now have to build consensus in a more complex and richer culture. The politicians and the mandarins can pull the levers they want but they no longer connect to anything. New Labour was elected on huge majorities but it didn't deliver strong government because power is something to be negotiated, not imposed.

Without PR other democratic reforms are just a technical fix. Democracy only matters if it is about choice between competing views of the good society and the good life. FPTP forces parties to compete on the same terrain. A political world based on PR bursts from sepia into colour. All of a sudden every vote and every voice matters. The Greens and others, who are shut out of Westminster despite support in the country, put the politics of social justice and sustainability on the agenda.

The demand is simple; that the British people are given a vote on whether to stick with FPTP or switch to PR. There are lots of systems but the one on the ballot paper would not be the choice of the political class but a jury of randomly selected citizens who, after an intensive but comprehensive education on voting systems, would select the best alternative. The referendum would be held on the day of the next election; this stops any accusations that it's an attempt to fix the result.

Who wants change, who wants modernisation, who wants an end to steam-age democracy and shift to a post-bureaucratic world in which politicians gain the trust of the people because they show that they trust them? If you do it won't be delivered from on high, power is never given away for free. It must be fought and struggled for. All of a sudden it's not just the anoraks. We might still live in a world of pluralism, open debate and consent building. It's called politics.